TGFB1 and polyostotic fibrous dysplasia: Anti-fibrotic mechanisms for PFD have been postulated to be mainly attributed to attenuating protein levels and signaling pathways of pro-fibrotic growth factors, including transforming growth factor (TGF)-β, platelet-derived growth factor (PDGF), and basic-fibroblast growth factor (bFGF) [7, 10, 11].